ContainerImage.Pinniped/internal/supervisor/server/server.go

538 lines
16 KiB
Go

// Copyright 2020-2022 the Pinniped contributors. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
// Package server defines the entrypoint for the Pinniped Supervisor server.
package server
import (
"context"
"crypto/rand"
"crypto/tls"
"fmt"
"net"
"net/http"
"os"
"os/signal"
"strconv"
"strings"
"sync"
"syscall"
"time"
"github.com/joshlf/go-acl"
appsv1 "k8s.io/api/apps/v1"
corev1 "k8s.io/api/core/v1"
apimachineryversion "k8s.io/apimachinery/pkg/version"
genericapifilters "k8s.io/apiserver/pkg/endpoints/filters"
kubeinformers "k8s.io/client-go/informers"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/pkg/version"
"k8s.io/client-go/rest"
"k8s.io/utils/clock"
configv1alpha1 "go.pinniped.dev/generated/latest/apis/supervisor/config/v1alpha1"
pinnipedclientset "go.pinniped.dev/generated/latest/client/supervisor/clientset/versioned"
pinnipedinformers "go.pinniped.dev/generated/latest/client/supervisor/informers/externalversions"
"go.pinniped.dev/internal/config/supervisor"
"go.pinniped.dev/internal/controller/supervisorconfig"
"go.pinniped.dev/internal/controller/supervisorconfig/activedirectoryupstreamwatcher"
"go.pinniped.dev/internal/controller/supervisorconfig/generator"
"go.pinniped.dev/internal/controller/supervisorconfig/ldapupstreamwatcher"
"go.pinniped.dev/internal/controller/supervisorconfig/oidcupstreamwatcher"
"go.pinniped.dev/internal/controller/supervisorstorage"
"go.pinniped.dev/internal/controllerinit"
"go.pinniped.dev/internal/controllerlib"
"go.pinniped.dev/internal/crypto/ptls"
"go.pinniped.dev/internal/deploymentref"
"go.pinniped.dev/internal/downward"
"go.pinniped.dev/internal/groupsuffix"
"go.pinniped.dev/internal/kubeclient"
"go.pinniped.dev/internal/leaderelection"
"go.pinniped.dev/internal/oidc/jwks"
"go.pinniped.dev/internal/oidc/provider"
"go.pinniped.dev/internal/oidc/provider/manager"
"go.pinniped.dev/internal/plog"
"go.pinniped.dev/internal/secret"
)
const (
singletonWorker = 1
defaultResyncInterval = 3 * time.Minute
)
func startServer(ctx context.Context, shutdown *sync.WaitGroup, l net.Listener, handler http.Handler) {
handler = genericapifilters.WithWarningRecorder(handler)
handler = withBootstrapPaths(handler, "/healthz") // only health checks are allowed for bootstrap connections
server := http.Server{
Handler: handler,
ConnContext: withBootstrapConnCtx,
ReadHeaderTimeout: 10 * time.Second,
}
shutdown.Add(1)
go func() {
defer shutdown.Done()
err := server.Serve(l)
plog.Debug("server exited", "err", err)
}()
shutdown.Add(1)
go func() {
defer shutdown.Done()
<-ctx.Done()
plog.Debug("server context cancelled", "err", ctx.Err())
// allow up to a minute grace period for active connections to return to idle
connectionsCtx, connectionsCancel := context.WithTimeout(context.Background(), time.Minute)
defer connectionsCancel()
if err := server.Shutdown(connectionsCtx); err != nil {
plog.Debug("server shutdown failed", "err", err)
}
}()
}
func signalCtx() context.Context {
signalCh := make(chan os.Signal, 1)
signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM)
ctx, cancel := context.WithCancel(context.Background())
go func() {
defer cancel()
s := <-signalCh
plog.Debug("saw signal", "signal", s)
}()
return ctx
}
//nolint:funlen
func prepareControllers(
cfg *supervisor.Config,
issuerManager *manager.Manager,
dynamicJWKSProvider jwks.DynamicJWKSProvider,
dynamicTLSCertProvider provider.DynamicTLSCertProvider,
dynamicUpstreamIDPProvider provider.DynamicUpstreamIDPProvider,
secretCache *secret.Cache,
supervisorDeployment *appsv1.Deployment,
kubeClient kubernetes.Interface,
pinnipedClient pinnipedclientset.Interface,
kubeInformers kubeinformers.SharedInformerFactory,
pinnipedInformers pinnipedinformers.SharedInformerFactory,
leaderElector controllerinit.RunnerWrapper,
) controllerinit.RunnerBuilder {
federationDomainInformer := pinnipedInformers.Config().V1alpha1().FederationDomains()
secretInformer := kubeInformers.Core().V1().Secrets()
// Create controller manager.
controllerManager := controllerlib.
NewManager().
WithController(
supervisorstorage.GarbageCollectorController(
dynamicUpstreamIDPProvider,
clock.RealClock{},
kubeClient,
secretInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
supervisorconfig.NewFederationDomainWatcherController(
issuerManager,
clock.RealClock{},
pinnipedClient,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
supervisorconfig.NewJWKSWriterController(
cfg.Labels,
kubeClient,
pinnipedClient,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
supervisorconfig.NewJWKSObserverController(
dynamicJWKSProvider,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
supervisorconfig.NewTLSCertObserverController(
dynamicTLSCertProvider,
cfg.NamesConfig.DefaultTLSCertificateSecret,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
generator.NewSupervisorSecretsController(
supervisorDeployment,
cfg.Labels,
kubeClient,
secretInformer,
func(secret []byte) {
plog.Debug("setting csrf cookie secret")
secretCache.SetCSRFCookieEncoderHashKey(secret)
},
controllerlib.WithInformer,
controllerlib.WithInitialEvent,
),
singletonWorker,
).
WithController(
generator.NewFederationDomainSecretsController(
generator.NewSymmetricSecretHelper(
"pinniped-oidc-provider-hmac-key-",
cfg.Labels,
rand.Reader,
generator.SecretUsageTokenSigningKey,
func(federationDomainIssuer string, symmetricKey []byte) {
plog.Debug("setting hmac secret", "issuer", federationDomainIssuer)
secretCache.SetTokenHMACKey(federationDomainIssuer, symmetricKey)
},
),
func(fd *configv1alpha1.FederationDomainStatus) *corev1.LocalObjectReference {
return &fd.Secrets.TokenSigningKey
},
kubeClient,
pinnipedClient,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
generator.NewFederationDomainSecretsController(
generator.NewSymmetricSecretHelper(
"pinniped-oidc-provider-upstream-state-signature-key-",
cfg.Labels,
rand.Reader,
generator.SecretUsageStateSigningKey,
func(federationDomainIssuer string, symmetricKey []byte) {
plog.Debug("setting state signature key", "issuer", federationDomainIssuer)
secretCache.SetStateEncoderHashKey(federationDomainIssuer, symmetricKey)
},
),
func(fd *configv1alpha1.FederationDomainStatus) *corev1.LocalObjectReference {
return &fd.Secrets.StateSigningKey
},
kubeClient,
pinnipedClient,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
generator.NewFederationDomainSecretsController(
generator.NewSymmetricSecretHelper(
"pinniped-oidc-provider-upstream-state-encryption-key-",
cfg.Labels,
rand.Reader,
generator.SecretUsageStateEncryptionKey,
func(federationDomainIssuer string, symmetricKey []byte) {
plog.Debug("setting state encryption key", "issuer", federationDomainIssuer)
secretCache.SetStateEncoderBlockKey(federationDomainIssuer, symmetricKey)
},
),
func(fd *configv1alpha1.FederationDomainStatus) *corev1.LocalObjectReference {
return &fd.Secrets.StateEncryptionKey
},
kubeClient,
pinnipedClient,
secretInformer,
federationDomainInformer,
controllerlib.WithInformer,
),
singletonWorker,
).
WithController(
oidcupstreamwatcher.New(
dynamicUpstreamIDPProvider,
pinnipedClient,
pinnipedInformers.IDP().V1alpha1().OIDCIdentityProviders(),
secretInformer,
plog.Logr(), //nolint:staticcheck // old controller with lots of log statements
controllerlib.WithInformer,
),
singletonWorker).
WithController(
ldapupstreamwatcher.New(
dynamicUpstreamIDPProvider,
pinnipedClient,
pinnipedInformers.IDP().V1alpha1().LDAPIdentityProviders(),
secretInformer,
controllerlib.WithInformer,
),
singletonWorker).
WithController(
activedirectoryupstreamwatcher.New(
dynamicUpstreamIDPProvider,
pinnipedClient,
pinnipedInformers.IDP().V1alpha1().ActiveDirectoryIdentityProviders(),
secretInformer,
controllerlib.WithInformer,
),
singletonWorker)
return controllerinit.Prepare(controllerManager.Start, leaderElector, kubeInformers, pinnipedInformers)
}
func startControllers(ctx context.Context, shutdown *sync.WaitGroup, buildControllers controllerinit.RunnerBuilder) error {
runControllers, err := buildControllers(ctx)
if err != nil {
return fmt.Errorf("cannot create run controller func: %w", err)
}
shutdown.Add(1)
go func() {
defer shutdown.Done()
runControllers(ctx)
}()
return nil
}
//nolint:funlen
func runSupervisor(ctx context.Context, podInfo *downward.PodInfo, cfg *supervisor.Config) error {
serverInstallationNamespace := podInfo.Namespace
dref, supervisorDeployment, supervisorPod, err := deploymentref.New(podInfo)
if err != nil {
return fmt.Errorf("cannot create deployment ref: %w", err)
}
opts := []kubeclient.Option{
dref,
kubeclient.WithMiddleware(groupsuffix.New(*cfg.APIGroupSuffix)),
}
client, leaderElector, err := leaderelection.New(
podInfo,
supervisorDeployment,
opts...,
)
if err != nil {
return fmt.Errorf("cannot create k8s client: %w", err)
}
clientWithoutLeaderElection, err := kubeclient.New(opts...)
if err != nil {
return fmt.Errorf("cannot create k8s client without leader election: %w", err)
}
kubeInformers := kubeinformers.NewSharedInformerFactoryWithOptions(
client.Kubernetes,
defaultResyncInterval,
kubeinformers.WithNamespace(serverInstallationNamespace),
)
pinnipedInformers := pinnipedinformers.NewSharedInformerFactoryWithOptions(
client.PinnipedSupervisor,
defaultResyncInterval,
pinnipedinformers.WithNamespace(serverInstallationNamespace),
)
// Serve the /healthz endpoint and make all other paths result in 404.
healthMux := http.NewServeMux()
healthMux.Handle("/healthz", http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
_, _ = writer.Write([]byte("ok"))
}))
dynamicJWKSProvider := jwks.NewDynamicJWKSProvider()
dynamicTLSCertProvider := provider.NewDynamicTLSCertProvider()
dynamicUpstreamIDPProvider := provider.NewDynamicUpstreamIDPProvider()
secretCache := secret.Cache{}
// OIDC endpoints will be served by the oidProvidersManager, and any non-OIDC paths will fallback to the healthMux.
oidProvidersManager := manager.NewManager(
healthMux,
dynamicJWKSProvider,
dynamicUpstreamIDPProvider,
&secretCache,
clientWithoutLeaderElection.Kubernetes.CoreV1().Secrets(serverInstallationNamespace), // writes to kube storage are allowed for non-leaders
)
buildControllersFunc := prepareControllers(
cfg,
oidProvidersManager,
dynamicJWKSProvider,
dynamicTLSCertProvider,
dynamicUpstreamIDPProvider,
&secretCache,
supervisorDeployment,
client.Kubernetes,
client.PinnipedSupervisor,
kubeInformers,
pinnipedInformers,
leaderElector,
)
shutdown := &sync.WaitGroup{}
if err := startControllers(ctx, shutdown, buildControllersFunc); err != nil {
return err
}
if e := cfg.Endpoints.HTTP; e.Network != supervisor.NetworkDisabled {
finishSetupPerms := maybeSetupUnixPerms(e, supervisorPod)
httpListener, err := net.Listen(e.Network, e.Address)
if err != nil {
return fmt.Errorf("cannot create http listener with network %q and address %q: %w", e.Network, e.Address, err)
}
if err := finishSetupPerms(); err != nil {
return fmt.Errorf("cannot setup http listener permissions for network %q and address %q: %w", e.Network, e.Address, err)
}
defer func() { _ = httpListener.Close() }()
startServer(ctx, shutdown, httpListener, oidProvidersManager)
plog.Debug("supervisor http listener started", "address", httpListener.Addr().String())
}
if e := cfg.Endpoints.HTTPS; e.Network != supervisor.NetworkDisabled { //nolint:nestif
finishSetupPerms := maybeSetupUnixPerms(e, supervisorPod)
bootstrapCert, err := getBootstrapCert() // generate this in-memory once per process startup
if err != nil {
return fmt.Errorf("https listener bootstrap error: %w", err)
}
c := ptls.Default(nil)
c.GetCertificate = func(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
cert := dynamicTLSCertProvider.GetTLSCert(strings.ToLower(info.ServerName))
defaultCert := dynamicTLSCertProvider.GetDefaultTLSCert()
if plog.Enabled(plog.LevelTrace) { // minor CPU optimization as this is generally just noise
host, port, _ := net.SplitHostPort(info.Conn.LocalAddr().String()) // error is safe to ignore here
plog.Trace("GetCertificate called",
"info.ServerName", info.ServerName,
"foundSNICert", cert != nil,
"foundDefaultCert", defaultCert != nil,
"host", host,
"port", port,
)
}
if cert == nil {
cert = defaultCert
}
if cert == nil {
setIsBootstrapConn(info.Context()) // make this connection only work for bootstrap requests
cert = bootstrapCert
}
return cert, nil
}
httpsListener, err := tls.Listen(e.Network, e.Address, c)
if err != nil {
return fmt.Errorf("cannot create https listener with network %q and address %q: %w", e.Network, e.Address, err)
}
if err := finishSetupPerms(); err != nil {
return fmt.Errorf("cannot setup https listener permissions for network %q and address %q: %w", e.Network, e.Address, err)
}
defer func() { _ = httpsListener.Close() }()
startServer(ctx, shutdown, httpsListener, oidProvidersManager)
plog.Debug("supervisor https listener started", "address", httpsListener.Addr().String())
}
plog.Debug("supervisor started")
defer plog.Debug("supervisor exiting")
shutdown.Wait()
return nil
}
func maybeSetupUnixPerms(endpoint *supervisor.Endpoint, pod *corev1.Pod) func() error {
if endpoint.Network != supervisor.NetworkUnix {
return func() error { return nil }
}
_ = os.Remove(endpoint.Address) // empty dir volumes persist across container crashes
return func() error {
selfUser := int64(os.Getuid())
var entries []acl.Entry
for _, container := range pod.Spec.Containers {
if container.SecurityContext == nil ||
container.SecurityContext.RunAsUser == nil ||
*container.SecurityContext.RunAsUser == selfUser {
continue
}
plog.Debug("adding write permission",
"address", endpoint.Address,
"uid", *container.SecurityContext.RunAsUser,
)
entries = append(entries, acl.Entry{
Tag: acl.TagUser,
Qualifier: strconv.FormatInt(*container.SecurityContext.RunAsUser, 10),
Perms: 2, // write permission
})
}
return acl.Add(endpoint.Address, entries...) // allow all containers in the pod to write to the socket
}
}
func main() error { // return an error instead of plog.Fatal to allow defer statements to run
defer plog.Setup()()
plog.Always("Running supervisor",
"user-agent", rest.DefaultKubernetesUserAgent(),
"version", versionInfo(version.Get()),
"arguments", os.Args,
)
// Discover in which namespace we are installed.
podInfo, err := downward.Load(os.Args[1])
if err != nil {
return fmt.Errorf("could not read pod metadata: %w", err)
}
ctx := signalCtx()
// Read the server config file.
cfg, err := supervisor.FromPath(ctx, os.Args[2])
if err != nil {
return fmt.Errorf("could not load config: %w", err)
}
return runSupervisor(ctx, podInfo, cfg)
}
func Main() {
if err := main(); err != nil {
plog.Fatal(err)
}
}
type versionInfo apimachineryversion.Info // hide .String() method from plog